Azo dye.



UNITED STATES PATENT OFFICE.

OSCAR GfINTI-IER AND LEOPOLI) HESSE, OF ELBERFELD, AND ARTHUR ZART. OF VOHWINKEL, GERMANY, ASSIGNORS TO FARBENFABRIKEN VORM. FRIEDR. BAYER & C0,, OF ELBERFELD, GERMANY, A CORPORATION OF GERMANY.

Patented Jan. 31,1911

AZO DYE.

982,952. Specification of Letters Patent.

No Drawing. Application filed April 19. 1910.

Serial No. 556,387.

of philosophy, chemists, citizens of the Gen man Empire, residing, respectively, at Freyastrasse 77, Elberfeld, Boltenlwrgstrasse .lClberfeld, and Yoi icstrasse 18, Vohwinkel,

Germany, have invented new and useful Improvements in Azo .l)yes,ot whichlhe following is a siecification.

This invention relates to the preparation of new azo dyestuffs which are obtained by combining in alkaline or neutral solution the diazo compoundsot' unsulfoi'iated nitroamins of the benzene series, especially, nitranilins and their derivatives 6. r]. 2-.nitro-4-acetylparaphenylenediamin, 4 nitro 2 :inisidin (()(.-ll,,:;\ll NO :lzQrat), 5-nitro-2-anisidin (OCH, ,:1:2:5), 5-nitro-i2- toluidin((1H,,.Kll,:N() :1:2:5),Q-chlorw 4-uitranilin, nitro-anthranilic acids, 2.t' -dil:romw-l-uitranilin etcl with substituted 2- :nuino-8naphtbal-(3-sulfonic acids, especia l ly Jl-alkylami nip, 2-arylaniino-. .Z-aralkylamino-S-naphtl\ol-tl-sulfimic acids and their derivatives substituted in 'l-position e. 5 the l.B-na )bthimidazol-S-oxyt'i-sult'onie acids, the 1.2 naphthothiazol t oxy (t sul't'onic acids etc.

The new dye tutt's are after being dried and pulverized in the shape of their alkaline salts dark powders soluble in water: yielding upon reduction with stannous chlorid and hydrochloric acid an nnsul'l'omlted benzene compound containing at least two amino groups and substituted T-amiuo flamino S-naphthol'- t3-sultonic acids. They produce on wool from an acid bath red to brown to black shades of good fastness to light and to milling.

To orderto illustrate the new process more fully the following example is given, the. parts being by weight: 168 parts of -lnitro-EZ-zmisidin are dissolved y boiling them in 1000 parts of a 20 per cent. hydrochloric acid and 700 parts of water. The solution is cooled to about 15 (,hby the addition of ice and is then diazot'ized by means of G9 parts of sodium nitrite. The diazo compound is then added at; 0 C.,

while stirring to an aqueous solution of 31.5 parts of Jphenyl-amino-8-naphthol-(i-snllonic. acid containing an excess of sodium carbomite. The combination is complete after a shorttime.

The dyestutf is isolated in the usual way. It is after being dried and pulverized in the shape of its sodium salt a dark powder soluble in crmcentratcd sulfuric acid with a violet-red color: yielding upon reduction with stannous chlorid and hydrochloric acid 'l.4--diamimi-anisol and T-amino-Q-phenylamino-S-naphthol-(i-sulfonic acid; and dyeing wool from an acid bath a full brown.

Ye claim:

1. The herein described new azo dyestuffs obtainable from unsulfonated nitroamins of the benzene series and substituted Q-amino- H-naphthol-6-snltonic acids which are after being dried and pulverized in the shape of their sodium salts dark powders, yielding upon reduction with stannousv chlorid and hydrochloric acid an ui'isulfonated benzene compound containing at least 'two amino groups and substituted 7-amino-2-amin0-8- naphthol-6sulfonic acids, and dyeing wool from red to brown to black shades, substantially as described.

2. The herein described new azo dyestutf obtainable from nitroaminoanisol and 2 phenylamiuo 5 naphthol t} sult'onic acid, which dye is after being dried and pulverized in the shape of its sodium salt a dark powder soluble in concentrated sulfuric acid with a violet-red color; yielding upon reduction with stannous chlorid and hydrochloric acid 2.-'l-dianiinoanisol and Tamino2-pl1e-' nyl-amino-8napht'holJS-sultonic acid: and dyeing wool brown shades, substantially as described.

in testimony whereof we have hereunto set our hands in the presence. of two subscribing witnesses.

OSCAR (HIX'lI'll llt. tn. 3.] ldCOlULl) lll'lSh'lC. .]'i,. s.] ARTHUR ZAIt'l. [1 sf] V itnesses:

O'rro KoNm, \VILLY KLEIN. 

